两道逻辑题!!!!!!!!!!!!!!!!

两道逻辑题，大家看看会做不？

1.Agricultural societies cannot exist without staple crops.Several food plants,such as kola andokra,are known to have been deomesticated in western Africa,but they are all supplemental,not staple,foods.All the recorded staple crops grown in westen Africa were introduced from elsewhere,beginning, at some unknown date, with rice and yams.Therefore,discovering when rice and yams were introduced into western Africa would establish the earliest date at which agricultural societies could have arisen there.

assumption 题

A.People in western Africa did not develop staple crops that they stopped cultivating once rice and yams were introduced.

B.There are no plants native to western Africa that, it domesticated, could serve as satple food crops.

答案是a。但我认为是b。???

2.Wolves generally avoid human settlements. For this reason, domestice sheep, though essentially easy prey for wolves , are not usually attacked by them. In hylantia prior to 1910,farmers nevertheless lost considerable numbers of sheep to wolves each year.Attributing this to the large number for wolves, in 1910 the government began offering rewards to hunters for killing wolves. From 1910 to 1915, the large numbers of wolves were killed. Yet wolf attacks on sheep increased significantly.

explain the increase in wolf attacks on sheep.

A.populations of deer and other wild animals that wolves typically prey on increased significantly in numbers from 1910 to 1915. 

B.After 1910 hunters shot and wounded a substantial number of wolves, thereby greatly diminishing these wolves' ability to prey on wild animals.

答案b。a 不可以吗？b中，猎人的捕杀怎会降低狼捕食野生的能力哩？

1.Agricultural societies cannot exist without staple crops.Several food plants,such as kola andokra,are known to have been deomesticated in western Africa,but they are all supplemental,not staple,foods.All the recorded staple crops grown in westen Africa were introduced from elsewhere,beginning, at some unknown date, with rice and yams.Therefore,discovering when rice and yams were introduced into western Africa would establish the earliest date at which agricultural societies could have arisen there.

assumption 题

A.People in western Africa did not develop staple crops that they stopped cultivating once rice and yams were introduced.

B.There are no plants native to western Africa that, it domesticated, could serve as satple food crops.

B。就算有native staple在western africa, 但是可能他们没发现。 而且这里还有一个时间的概念，B中没有给出时间，如果这些是rice and yams到了那边的之后才有的呢？就算没有B的assumption，还是可以有最后的结论，如果没有A， 那就得不出最后的结论了，LZ好好体会一下。

2.Wolves generally avoid human settlements. For this reason, domestice sheep, though essentially easy prey for wolves , are not usually attacked by them. In hylantia prior to 1910,farmers nevertheless lost considerable numbers of sheep to wolves each year.Attributing this to the large number for wolves, in 1910 the government began offering rewards to hunters for killing wolves. From 1910 to 1915, the large numbers of wolves were killed. Yet wolf attacks on sheep increased significantly.

explain the increase in wolf attacks on sheep.

A.populations of deer and other wild animals that wolves typically prey on increased significantly in numbers from 1910 to 1915. 

B.After 1910 hunters shot and wounded a substantial number of wolves, thereby greatly diminishing these wolves' ability to prey on wild animals.

答案b。a 不可以吗？b中，猎人的捕杀怎会降低狼捕食野生的能力哩？

A。狼的prey如果多了的话，狼袭击家禽的事应该少了才对。
B。狼是群居动物，数量少会影响它们的攻击力。 而且不管这对不对，答案中给出了你就当是真的来看就好， 能结实了最后的结论就是正确答案。